Magnetically releasable latch



Feb. 25, 19%, F. c. scHocH MAGNETICALLY RELEASABLE LATCH Filed Oct. 22,1934 neg Patented Feb. 25 1936 UNITED STATES PATENT ()FFICF.-

2,031,738 MAGNETIC ALLY RELEASABLE LATCH Fred C. Schoch, Oak Park, Ill.Application October 29, 1934, Serial No. 750,447

5Q Claims.

This invention relates to improvement in latch constructions for doors,windows and other closures and refers specifically to a magneticallyreleasable latch for automobile doors or the like.

It frequently happens particularly in the case of automobiles, thatvaluables, packages or the like are, locked in the car. A thief,possibly not interested in the theft of the automobile itself, orfrustrated in his attempt to steal the car, may appropriate thevaluables or packages within the car by merely breaking a window,inserting his hand through the broken window to manipulate the insidelatch handle, and thus open the door. In my invention means is providedwhereby the inside latch handles of all of the doors of the car may berendered inoperative to open said doors while the car ignition system isturned off. Hence, a thief breaking the glass of such a door must enterand leave the car through the broken window. As a matter of humanpsychology, a wary thief is disinclined to enter a compartment fromwhich he cannot quickly leave in the event of his detection.Consequently, inasmuch as the automobile thief, in the nature of things,ordinarily has only a relatively short time in which to perpetrate hispilfering and knowing that his operations may be suddenly. detected, themiscreant will be reluctant to undergo the excessive risks he iscompelled to take to steal from an automobile protected by my invention.

Another object of my invention resides-in the economical construction ofthe automatically restrained latch and the ease with which the same maybe applied to existing automobile door latches.

Other objects and advantages of my invention will be apparent from theaccompanying drawing and following detail description.

In the drawing, Fig. 1 is a diagrammatic, perspective view of mymagnetically controlled latch as applied to an automobile door, partsbeing eliminated for the sake of clarity.

Fig. 2 is a schematic wiring diagram of the mechanism shown in Fig. 1.

Referring in detail to the drawing, I indicates diagrammatically aportion of an automobile door mounted in the usual frame 2, only aportion of .which is shown. Although my invention is illustrated anddescribed in conjunction with an automobile door, in connection withwhichit is particularly well suited, it may also be used in conjunctionwith other closures such as windows, house doors and the like.

- The reference numeral 3 indicates fragmentary portions of the outsidepanel of the automobile door I, and positioned within said door andbehind the panel 3 is a conventional type latch bolt 4 mounted in guide5 which, in turn, may be disposed upon plateli. A recess or keeper maybe provided in the face plate I of frame 2, said keeper-being adapted toreceive the projecting end 8 of latch bolt 4.

- An arm 9 may comprise an integral portion of latch bolt 4 and mayextend downwardly from said latch bolt, said arm being provided with acontact lug I0 at its extremity. A shank Il may be transverselypositioned within door I and may carry acollar Ilat its innermost end.Arm I3 may comprise an integral portion of collar I2 and as will behereinafter more fully described, said arm, upon rotation of shank II,is adapted to contact lug III and thus shift latch bolt 4 so as toretract the end 8 of said latch from the keeper. The outer end of shankI I may project outwardly from panel 3 and may carry a-handle' I4.

My present invention may be utilized in conjunction with theusualautomobile door latch operating mechanism wherein a lock (notshown) is carried by shank I I, which may be operated by a key insertedin the key hole I5 provided at the outer end of said shank. However, itis to be understood that my present invention may be utilized with othertypes of latch operating devices, for instance, such as that-shown in myco-pending application, Serial No. 746,666, filed October 3, 1934. 1

A plate I6 may also be positioned within door I, said plate. carryingupon its inner surface a bridge-like supporting member II. A pin I8 maybe journalled in both the members I! and in plate I6 and may carry anarm I9 which is rigidly attached to said pin, said arm being positionedbetween member I! and plate I6. A handle 20 may be secured to theopposite end of pin I8, said handle being positioned on the outer sideof the inner panel (not shown) of the-door I. A link 2| may be pivotallyconnected as at 22 to arm IS, the opposite end of said link beingpivotally connected to the end of latch bolt 4 as at 23. The connectionbetween link 2| and latch bolt 4 is of the lost-motion type wherein aslot 24 is provided in the end of latch bolt 4 which may permit theindependent operation of handle I4 in retracting latch bolt 4 withoutdisturbing the remaining mechanism associated with link 2 I'. .50

In normal operation latch bolt 4 may either be shifted to remove the end8 thereof from the keeper by means of handle I4, or said latch bolt maybe shi ted by means of handle 20 from within the automobile. A spring 25connected to plate -4 to closed position within the keeper, and a bladespring 23'mounted at one end upon member I1 and engageable'at the otherend with an indented portion 21 of the element l9, may serve to returnarm l9 andhandle 20 to its original position when handle 20 has beenmanipulated to retract latch bolt 4. v

A pin 21 may be transversely journalled in plate IS, the outer end ofsaid pin carrying handle 28 which may be operable from the inside of theautomobile. The opposite end of pin 21 may carry arm 29 which mayberigidly secured to said pin. The end of arm 29 may carry an oflset lug30, the function of which will be hereinafter de- Y scribed. A secondarm 3| may be loosely mounted at one end upon pin 21 between arm 29 andplate 13. A coil spring 32 is connected. between arm 3| and plate l3insuch a manner as to urge arm 3| in a counterclockwise direction asviewed in Fig. 1. End 33 of arm 3| may be bent at right angles to saidarm and when said arm is in the position shown in Fig. 1, the end 33thereof is disposed adjacent arm IS.

A lug 34 may be secured to plate IE but may be electrically insulated byinsulator 35 from said plate, it being understood that plate i3 and lug34 are of metallic construction wherein insulator 35 may comprise fiber,hard rubber, Bakelite or the like. Lug 3 4v may be bent intermediate itslength so as to provide an outwardly extending bracket 35 which'mayproject at' an angle to the face of plate IS. A metallic, sleeve 33 maybe secured to the projecting lug 35 and may be disposed at an angle tothe member 35 and substantially parallel to the plane of plate |3. A pin31 I having a bevel end 38 may be slidably positioned within sleeve 33and a coil spring 39 may be positioned within sleeve 33 and may be sooperatively associated with pin 31 as to normally urge said pin towardthe left as viewed in Fig. l.

The opposite end of pin 31 may comprise button 40 which may be made ofsteel or iron or any other magnetic material. A solenoid 4| may bemounted upon plate I3 and the wires constituting the same may be .woundaround the core 42 constructed of magnetic material. The. disposition ofsolenoid 4| is so arranged with respect to pin 31 as to position core 42and pin 31 coaxial, the movement of pin 31 being. in a line with thelongitudinal axis of core 42.

In operation, when the door I is in normal closed position as indicatedin Fig. 1, latch bolt 4, arm l9, handle 20 and pin 31 will be in theposition shown in the drawing.

Arm 3| in its normal position, that is, its unlocked position, will berotated to its extreme counterclockwise position by spring 32. In otherwords, the bent end 33 of arm 3| will be above the bevelled end of pin31. When it is desired to lock the mechanism so that latch bolt 4 cannotbe retracted by handle handle 23 may be rotated in a clockwisedirection. This rotation, of course, is imparted to arm 29 and theofiset lug 30 carried by said arm contacts the upper edge of arm 3|. Ashandle 28 is rotated to the right or in a clockwise direction, arm 23carries arm 3| in the same direction and the lower edge of the bent end33 of arm 3| contacts the bevel 33 and forces pin 31 to the rightagainst the compression of spring 39.

When arm 28 has been, so rotated as to bring the upper edge of the bentend.33 below pin 31,

said pin, under the influence of spring 39 moves to the left and'abovethe bent end 33 preventing I 2,081,788 '3 and latch bolt 4 may normallyurge latch bolt counterclockwise movement of arm 3|. It can readily beseen that as handle 23 has moved arm 3| to this position, said handle isrendered inoperative to further control arm 3|. When arm 3| is in thisposition the bent end 33 of said arm is disposed adjacent the end 01'arm l9 and. con-- sequently, movement of said arm in a counter- "lead43. \The opposite end of said coil may be connected by means ofconductor 44 to plate 33. which as has been hereinbefore described, isinsulated from plate l3.

Referring particularly to Fig. 2, a'schematic drawing of the wiringsystem is shown wherein 43 indicates the storage battery or source ofelectricity for the automobile. Thenegative end of said battery may begrounded as shownat 43. The positive side of the battery may beconnected through switch 41 to the spark coil and distributor indicateddiagrammatically 'at 43.

The high tension side of the distributor may connect to the spark plugsof the automobile indicated diagrammatically at- 49. Of course, theopposite sides of the spark plugs are grounded as shown at 53. Conductor43 mayconnect that side of ignition switch ,41 which is opposite to thebattery 43 to coil or solenoid 4|. The opposite side of coil 4| may beconnected by conductor 44 to 1113 33.

In operation, when handle 20 is rendered inoperative in so far as theretracting-of latch bolt. 4 is concerned, arm 3| will be in the positionshown in Fig. 1 and the bent portion 33 of said arm is held againstcounterclockwise rotation by means of the end of pin 31. Consequently,the bent portion 33 and the'end of pin 31 are in contact. Hence, whenthe ignition switch 41 is closed, a circuit:may be traced from battery45 through switch 41, conductor 43, coil 4|, conductor 44,

, clockwise direction is prevented thereby renderv member 31, member 3|and the ground, thereby providing a complete circuit through coil 4|.When coil 4| is thus energized its magnetic core 42 is energized ormagnetized, and member 31 being disposed adjacent the endof said core ismagnetically attracted.

It can 'readily be seen by reference to Fig. 1, that when button 40 isattracted by core 42, pin 31 will move to the right against thecompression of spring 33. In so moving the end 33 of said pin is removedas an obstruction to the bent portion 33 of arm 3| and, acting under theinfluence of spring 32, said arm is moved in a counterclockwisedirection. When the arm 3| so moves arm |9 will be free to move inacounterclockwise direction when force is applied to handle 20' therebypermitting latch bolt 4 to be retracted from the keeper. Of course, whenarm 3| moves the limit of its counterclockwise motion,

under the impulse of spring 32, the bent portion .33 of said arm breakscontact with the end of pin 31 and, hence, the circuit through coil 32is broken, core 42 is demagnetized, and pin 31 acting 'under theinfluence of spring 33, moves to the the car, lock I3 is properlymanipulated to perthe car the ignition may be turned on whichactioncompletes the electrical circuit through solenoid 4| as has beenhereinbefore described and releases arm 3! from the position shown inFig. 1.

It is to be understood, of course, that the remaining doors of theautomobile may all be provided with the same type magnetically operatedlatch mechanism and that the various leads corresponding to lead 43 mayall be connected to a common source adjacent the ignition switch 41.Hence, after all of the handles 28 have been so set as to rotate arm 3|to its locking position, all of the arms corresponding to arm 3i may besi multaneously released by turning on the ignitioninasmuch as all ofthe coils corresponding to solenoid 4! are connectedin parallel.

lock and only one of the latch bolts corresponding to latch bolt 4 'willhave a lost motion connection i with the links corresponding to link 21,since,

there should be no occasion to have the outside door handles of theremaining doors of the car independently'operable with respect to theinside handles.

I claim as my invention:

1. In a device of the class described, the combination of a slidableautomobile door latch bolt with means for moving said latch bolt fromlatching position, comprising a handle operated arm operativelyconnected to said latch bolt, means for restraining movement of said armcomprising a spring operated swingable lug, means for manually disposingsaid lug adjacent said arm, and magnetic means for releasing said lugwhereby said lug acting under the influence of said spring swings fromitsposition adjacent said arm.

2. In a device of the class described, the combination of a slidableautomobile door latch bolt with means for moving said latch bolt fromlatch ing position, comprising a handle operated arm 'operativelyconnected to said latch bolt, means rent, a spring urged plungerdisposed adjacent the core of said'solenoid, said plunger beingnormally.

urged by its associated spring to a position to prevent movement of saidlug in response to its associated spring.

3. In a device of the class described, the combination of a slidableautomobile door latch bolt with meansfor moving said latch bolt fromlatching position, comprising a handle operated arm operatively'connected to said latch bolt, means for restraining movement of said armcomprising a 7 lug whereby said lug acting under the influence of i saidspring swings from its position adjacent said arm, said magnetic meanscomprising a solenoid connected to the ungrounded side of a source ofelectric current, an ungrounded spring urged plunger disposed adjacentthe core of said solenoid, said plunger being normally urged by itsassociated spring away from said core, said plunger making contact withsaid lug to prevent movement of said lug in response to its associated.spring, said lug being grounded whereby said plunger is grounded whensaid lug is in restraining position, said plunger being connected tosaid solenoid whereby said solenoid is energized when the automobileignition system is turned on.

4. In a device of the class described, the combination of a slidableautomobile door latch bolt with means on the outside and means on theinside of said door for moving said latch bolt from latching position,said inside means comprising a handle operated arm operatively connectedto said latch bolt, means for restraining movement bination of aslidable automobile door latch bolt with means on the outside and meanson the inside of said door for moving said latch bolt from latchingposition, said inside means comprising a handle operated arm operativelyconnected to said latch bolt through a lost motion connection wherebysaid outside and inside latch bolt moving means operate independently,means for restraining movement of said arm comprising a spring operatedswingable lug disposed adjacent said arm, and magnetic means forreleasing said lug whereby said lug acting under the influence of saidspring swings from its position adjacent said arm. FRED C. SCHOCH.

